| 摘要 |
P.C. 6307 VEIN DISTENTION SYSTEM Apparatus for the distention and irrigation of a saphenous vein which is being tested prior to use as a coronary or peripheral bypass graft includes a specially-configured cannula for insertion into the vein, and a pressure-limiting device having a resilient membrane reservoir which limits the hydrostatic pressure delivered to the vein to a predetermined level. The device is connected between the cannula inserted into the vein and a syringe filled with irrigation fluid. As fluid is delivered under pressure from the syringe the membrane reservoir fills with fluid and inflates within a specified range of pressures so that if excessive force is applied to the syringe, the membrane inflates, and the pressure transmitted to the vein cannot exceed a predetermined maximum pressure. A stopcock connected between the syringe and the membrane allows the membrane to be pressurized with the contents of the syringe. With the membrane filled and pressurized, the stopcock is closed, allowing the membrane to act as a reservoir which irrigates the vein at a constant, controlled pressure without further use of the syringe. The cannula has a tapered and bevelled tip which allows easy insertion into the vein, and a sloping shoulder just proximal to the tip which provides a convenient site for firmly securing the vein to the cannula with a ligature. |
